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OK to use synthetic oil ?

#1

J

jcworks

My TORO zero turn mower has Kawasaki 23 hp engine. 270 hours on it. 10 Years old. Been using CASTROL 10w30 or 20w50 in it, conventional oil. I've been thinking about maybe running synthetic in it this spring. Heck, everything else seems to be running ir. Got any thoughts on that anyone? I don't think I'd want to go down to 5w30 and don't know if synthetic comes in 10w30 or some such.


#2

Scrubcadet10

Scrubcadet10

I'd recommend Kawasaki K-TECH, it's synthetic blend and is formulated for small air cooled engines. I service several commercial Z turns with well over 3K hours on the clock with it. since new....
If you're dead set with full synthetic, i'd look no further than Amsoils 10w30 small engine oil https://www.amsoil.com/p/amsoil-10w-30-100-synthetic-small-engine-oil-ase/


#3

M

mechanic mark



#4

A

Aquadisiac

My TORO zero turn mower has Kawasaki 23 hp engine. 270 hours on it. 10 Years old. Been using CASTROL 10w30 or 20w50 in it, conventional oil. I've been thinking about maybe running synthetic in it this spring. Heck, everything else seems to be running ir. Got any thoughts on that anyone? I don't think I'd want to go down to 5w30 and don't know if synthetic comes in 10w30 or some such.

My 2017 eXmark Radius S zero turn has a Kohler engine on it. My manual says it can use either regular 10W-30 engine oil or fully synthetic 10W-30 engine oil. I have used both (not together).
I decided that from now on it will only get full synthetic oils. No reason other than it is getting harder to find a non synthetic oil.
I have only used the stated grade of 10W-30 oils and will continue to do that, just full synthetic from here on out.
I change my oil and filter after my last mowing of the year and sharpen my blades and lube the chassis, then it’s ready for action come springtime.


#5

rhiebert

rhiebert

Back in the day when I had small equipment like that, ie. rototiller, etc. I would put the used AMSOIL from my half-ton in them but when AMSOIL's "Small engine synthetic" became available it was a no-brainer.

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#6

O

Oddjob

Not exactly on point, but worth noting when talking about using synthetic oil: The conventional dinosaur stuff works better for breaking in new rings. Otherwise, I only use synthetic.


#7

I

ILENGINE

Not exactly on point, but worth noting when talking about using synthetic oil: The conventional dinosaur stuff works better for breaking in new rings. Otherwise, I only use synthetic.
Tell that to the equipment manufacturers that use synthetic straight from the factory in new equipment. Kohler dealers don't even receive conventional oil from their distributors anymore. The conventional Kohler 10w30 supercedes to the full synthetic version.


#8

7394

7394

New Corvettes same way.. Full Syn from day 1.


#9

Glades Cat

Glades Cat

Motor oil is always a slippery subject.
It’s a crude, but necessary topic and Oil-ways welcome here.
No room for synthetic conversation on this matter.
The best way to find the truth about oil is to drill through surface chaff.
Most oil company’s failure comes from losing their liquid assets.
Remember...we ain’t fracking lying here.


#10

O

Oddjob

Motor oil is always a slippery subject.
It’s a crude, but necessary topic and Oil-ways welcome here.
No room for synthetic conversation on this matter.
The best way to find the truth about oil is to drill through surface chaff.
Most oil company’s failure comes from losing their liquid assets.
Remember...we ain’t fracking lying here.
Got lubricated on Christmas Eve? Thanks for the highly refined comment, Glades Cat, and Merry ChrIstmas to everyone.


#11

J

JD_Driver

My TORO zero turn mower has Kawasaki 23 hp engine. 270 hours on it. 10 Years old. Been using CASTROL 10w30 or 20w50 in it, conventional oil. I've been thinking about maybe running synthetic in it this spring. Heck, everything else seems to be running ir. Got any thoughts on that anyone? I don't think I'd want to go down to 5w30 and don't know if synthetic comes in 10w30 or some such.

At this point, you’re doing your engine a disservice by not using synthetic oil. It’s a much better product than conventional oil. There is no downside other than cost.


#12

R

Ronni

My TORO zero turn mower has Kawasaki 23 hp engine. 270 hours on it. 10 Years old. Been using CASTROL 10w30 or 20w50 in it, conventional oil. I've been thinking about maybe running synthetic in it this spring. Heck, everything else seems to be running ir. Got any thoughts on that anyone? I don't think I'd want to go down to 5w30 and don't know if synthetic comes in 10w30 or some such.
Synthetic motor oil was invented by the Germans in WWII because they couldn’t get the supply otherwise. Synthetic these days has better protections for extreme conditions and it costs more. Regular motor oil will protect your engine just fine as long as you maintain your engine according to the owners manual and it costs less.


#13

SirMowzalot

SirMowzalot

I'd recommend Kawasaki K-TECH, it's synthetic blend and is formulated for small air cooled engines. I service several commercial Z turns with well over 3K hours on the clock with it. since new....
If you're dead set with full synthetic, i'd look no further than Amsoils 10w30 small engine oil https://www.amsoil.com/p/amsoil-10w-30-100-synthetic-small-engine-oil-ase/
+1 on Amsoil, especially for cold weather stuff.


#14

Moparjoe499

Moparjoe499

My TORO zero turn mower has Kawasaki 23 hp engine. 270 hours on it. 10 Years old. Been using CASTROL 10w30 or 20w50 in it, conventional oil. I've been thinking about maybe running synthetic in it this spring. Heck, everything else seems to be running ir. Got any thoughts on that anyone? I don't think I'd want to go down to 5w30 and don't know if synthetic comes in 10w30 or some such.
Just use regular oil and put in a bottle of slick 50.


#15

J

J.D. Dave

I have a Generac 15KW standby generator air cooled with 992cc V twin engine, would it be ok to use the oil mentioned above (Amsoil/Kawasaki) and which one would be better?


#16

B

BTBO

My TORO zero turn mower has Kawasaki 23 hp engine. 270 hours on it. 10 Years old. Been using CASTROL 10w30 or 20w50 in it, conventional oil. I've been thinking about maybe running synthetic in it this spring. Heck, everything else seems to be running ir. Got any thoughts on that anyone? I don't think I'd want to go down to 5w30 and don't know if synthetic comes in 10w30 or some such.
I have a scag liberty z with the Kawasaki engine. Changed the factory oil @ 7 hrs using Mobil 1 20W/50. Last year I started using Valvoline synthetic racing oil 20W/50 (black bottle) because of the higher zinc content, as well as in my Troybilt push mower with Honda GCV 160 using 10W/30. I get it online via Walmart. Good stuff.


#17

B

Bushbunnie

My TORO zero turn mower has Kawasaki 23 hp engine. 270 hours on it. 10 Years old. Been using CASTROL 10w30 or 20w50 in it, conventional oil. I've been thinking about maybe running synthetic in it this spring. Heck, everything else seems to be running ir. Got any thoughts on that anyone? I don't think I'd want to go down to 5w30 and don't know if synthetic comes in 10w30 or some such.
what for? if it 's been good for ten years it should be good for 10 more.


#18

M

MartinR

My TORO zero turn mower has Kawasaki 23 hp engine. 270 hours on it. 10 Years old. Been using CASTROL 10w30 or 20w50 in it, conventional oil. I've been thinking about maybe running synthetic in it this spring. Heck, everything else seems to be running ir. Got any thoughts on that anyone? I don't think I'd want to go down to 5w30 and don't know if synthetic comes in 10w30 or some such.
If you have done that many hours on 10/20w30 oil I would stick to it, using synthetic now could cause a problem. I used to use SAE30 in the FH series Kawasaki's with out problems for hundreds of hours but the new ones are specifying semi synthetic, involves more cost and you can never be to sure to what benefit until it goes wrong.


#19

G

Gord Baker

My TORO zero turn mower has Kawasaki 23 hp engine. 270 hours on it. 10 Years old. Been using CASTROL 10w30 or 20w50 in it, conventional oil. I've been thinking about maybe running synthetic in it this spring. Heck, everything else seems to be running ir. Got any thoughts on that anyone? I don't think I'd want to go down to 5w30 and don't know if synthetic comes in 10w30 or some such.
Stick with what you are using now. You may get many oil leaks changing to Synthetic. 10w30.


#20

Z

zrxkawboy

I’ve been using synthetic oil in small engines for 25 years.


#21

C

crazy charlie

My TORO zero turn mower has Kawasaki 23 hp engine. 270 hours on it. 10 Years old. Been using CASTROL 10w30 or 20w50 in it, conventional oil. I've been thinking about maybe running synthetic in it this spring. Heck, everything else seems to be running ir. Got any thoughts on that anyone? I don't think I'd want to go down to 5w30 and don't know if synthetic comes in 10w30 or some such.
Be very careful about switching from conventional to synthetic on any "not new" engine. Synthetic oils do not have the qualities and additives that keep the gaskets plump and sealed like conventional oils do.I am living proof that trying to take better care of my engines by switching to synthetic did nothing more than start a dripping leak where there was previously no leak.This 1st happened on a 100k mile Jeep which had a privileged babied life .Thought it would be a good idea to switch to synthetic at that time and I immediately discovered that where I may have had some slight seepage ,which is common an gaskets, turned into an immediate leak.I changed the synthetic out immediately within a a few days.The new leak improved with the use of conventional oil however I had slightly leaking gaskets for the next 100k miles.My next Jeep owned from new I used conventional oil except in the cold winter months where my remote start would not crank enough times to start the Jeep with conventional oil so I would schedule a synthetic change just before the cold weather hit so the engine would crank easier with the synthetic and remote start would function.The motor is currently at 150k and I just did the synthetic change ,as I always have ,and noticed that my valve covers started leaking for the 1st time so the synthetic has gotten me again. I think I will add some "stop leak" to the synthetic before changing it to see if any improvement.Stop leak contains concentrated additives that are found in conventional oils so I will give it a try .That being said,I would recommend a synthetic blend over a full synthetic for any engine that is not new.
Now as far as new engines that call for synthetic, they are manufactured with different type of seals and gaskets that are more compatible with synthetic oil use.Charlie


#22

B

bnicol456

I'd recommend Kawasaki K-TECH, it's synthetic blend and is formulated for small air cooled engines. I service several commercial Z turns with well over 3K hours on the clock with it. since new....
If you're dead set with full synthetic, i'd look no further than Amsoils 10w30 small engine oil https://www.amsoil.com/p/amsoil-10w-30-100-synthetic-small-engine-oil-ase/
I can't imagine why a superior product would be discouraged. I have used full synthetic in my mower (and car) since the first change. Walmart sells synthetic at a great price and it is highly rated.


#23

B

barny57

My TORO zero turn mower has Kawasaki 23 hp engine. 270 hours on it. 10 Years old. Been using CASTROL 10w30 or 20w50 in it, conventional oil. I've been thinking about maybe running synthetic in it this spring. Heck, everything else seems to be running ir. Got any thoughts on that anyone? I don't think I'd want to go down to 5w30 and don't know if synthetic comes in 10w30 or some such.
I think most the oil nowadays is a blend


#24

Scrubcadet10

Scrubcadet10

I can't imagine why a superior product would be discouraged. I have used full synthetic in my mower (and car) since the first change. Walmart sells synthetic at a great price and it is highly rated.
$13.00 a quart for amsoil, or $6 a quart for K-Tech from my John Deere dealer.
Several commercial mowers running over 3k hours, on KTech with no usage between changes is good enough for me and the customer.


#25

J

jcworks

I'd recommend Kawasaki K-TECH, it's synthetic blend and is formulated for small air cooled engines. I service several commercial Z turns with well over 3K hours on the clock with it. since new....
If you're dead set with full synthetic, i'd look no further than Amsoils 10w30 small engine oil https://www.amsoil.com/p/amsoil-10w-30-100-synthetic-small-engine-oil-ase/
Scrubcadet10, after reading all these posts I'm torn between continue using the regular Castrol conventional oil I've always used or go with the Kawasaki blend. Two local dealerships all told me using synthetic was ok. BUT, they've told me totally incorrect info on a trans axle issue I had. They had no clue on that as to what was wrong and they told me everything was fine. It took a lot of back and forth between me and Bertsmobile1 on here, and talking to a Hydro Gear rep to figure it out...which turned out to be so simple. So, my main concern is the engine is a 2013. The manual just says 10w30 - 20w50. It does not even mention synthetic at all. In 2013 perhaps the synthetic craze was not as strong as it is today; or maybe those engines of 2013 were not spec-ed out for synthetics. Who knows.


#26

N

nbpt100

Tell that to the equipment manufacturers that use synthetic straight from the factory in new equipment. Kohler dealers don't even receive conventional oil from their distributors anymore. The conventional Kohler 10w30 supercedes to the full synthetic version.
That is a good point. How do they justify it right from the start? Could one assume they both work to break in the engine, just one is a bit quicker. They figure many will not even bother to do a break in oil change so they just go with the syn right from the factory and keep everything a bit simpler. I am just musing.


#27

T

TheWB

Tell that to the equipment manufacturers that use synthetic straight from the factory in new equipment. Kohler dealers don't even receive conventional oil from their distributors anymore. The conventional Kohler 10w30 supercedes to the full synthetic version.
Kohler oil change kits are provided by Amsoil. I have run synthetic in everything since new, all Amsoil.


#28

P

pwardxe126

My TORO zero turn mower has Kawasaki 23 hp engine. 270 hours on it. 10 Years old. Been using CASTROL 10w30 or 20w50 in it, conventional oil. I've been thinking about maybe running synthetic in it this spring. Heck, everything else seems to be running ir. Got any thoughts on that anyone? I don't think I'd want to go down to 5w30 and don't know if synthetic comes in 10w30 or some such.
Switched my Kawasaki fh721v from conventional 20w50 to vanguard 15w50 full synthetic. Noticed smoother running and better oil pressure when the engine gets warmed up.


#29

grumpyunk

grumpyunk

If your engine does not need synthetic to protect for extreme heat or slow flow when cold, then you can use conventional oil without any problems. OTOH, if you want to spend more per oil change, synthetic is perfectly fine to use.
The engine was designed with conventional oil as the prospective lubricant. It should do fine. Synthetic will not buy anything unless you reach temperature extremes where regular oil would tend to degrade.
I have yet to use any synthetic in my Kohler CVs, with conventional 10W30 as the spec'd lube. They have lasted since 1988 and 1997 respectively, don't knock or use oil between changes. I do not baby them, as they were designed to run at about 3k rpm for hours, and they do fine. When drained, the oil is still brown, not black. I use any brand, whatever is on the shelf. I have used Stens filters without problem, along with some from auto parts stores that matched.
This is not rocket science, and the oils today have better additive packages than when the engines were designed.
If you want to spend money on very very high quality oils, have at it. You are just lining the pockets of those who sell that product. Check with "Project Farm" YT channel for unbiased comparisons of oil brands. You may be surprised at which seem to perform better than some usual suspects. Oil should not cost $10/qt. If it does, a LOT of that is in profit.
IMO.
tom


#30

Scrubcadet10

Scrubcadet10

Scrubcadet10, after reading all these posts I'm torn between continue using the regular Castrol conventional oil I've always used or go with the Kawasaki blend. Two local dealerships all told me using synthetic was ok. BUT, they've told me totally incorrect info on a trans axle issue I had. They had no clue on that as to what was wrong and they told me everything was fine. It took a lot of back and forth between me and Bertsmobile1 on here, and talking to a Hydro Gear rep to figure it out...which turned out to be so simple. So, my main concern is the engine is a 2013. The manual just says 10w30 - 20w50. It does not even mention synthetic at all. In 2013 perhaps the synthetic craze was not as strong as it is today; or maybe those engines of 2013 were not spec-ed out for synthetics. Who knows.
10w30 Synthetic Blend, like KTech should cause no issues.


#31

I

ILENGINE

That is a good point. How do they justify it right from the start? Could one assume they both work to break in the engine, just one is a bit quicker. They figure many will not even bother to do a break in oil change so they just go with the syn right from the factory and keep everything a bit simpler. I am just musing.
A lot of that thinking about synthetic oil would not allow proper break-in was false. Just the engine manufacturers not committing to the new oils even though a lot of synthetic oils start with the same refined base as the conventional oil they are replacing. Use of conventional oils for the first 50 hours to aid break-in has been removed from the owners manuals. And changing the break-in oil at 5 hours has been eliminated on engines with oil filters,because the break-in debris gets filtered. So the interval is now to go by the first recommended oil change interval so 50-100 hours. Almost all vehicles come from the factory with synthetic oil in the engine. Auto engines don't even have a break-in oil change, and basically never did. My 2011 Ram 1500 uses synthetic oil in everything but the engine. And the reason it doesn't use synthetic in the engine is because the synthetics in the 5w20 oils don't meet the Chrysler oil specs,

Kohler oil change kits are provided by Amsoil. I have run synthetic in everything since new, all Amsoil.
The Kohler synthetic oil change kit sourced from Amsoil and has a 300 hour change interval, which in most cases may be excessive. The old 25 357 06-S conventional oil now has been replaced with 25 357 64-S full synthetic. So Kohler doesn't even offer a conventional oil even outside of the synthetic oil service kit that they are pushing sourced from Amsoil.


#32

T

tlcstat

Conventional Oil is paraffin oil and paraffin equals sludge. I don't need to break an engine in with sludge. Plus with modern metallurgy break-in isn't necessary. I use Rotella T6 5w40 In my briggs engines and also in my generator. The difference is in the detergent package. Rotella is a truck engine oil that uses a longer lasting detergent. I have two riders over 10yrs old that run perfect and don't have any of the problems that I read about here. I change the oil every couple of seasons. No sense in buying extended interval oil and over servicing the equipment. Thats it from a truck mechanic's point of view.


#33

B

ba63

Just my opinion and I am not going to argue about it because it’s his machine and he can do as he pleases with it but the only real benefit I could understand for wanting to change from conventional to synthetic is if you forget or dislike changing your oil. If your using a decent quality conventional oil and changing it on a regular schedule, why spend more money on the same amount of oil just to say your running synthetic? The only times I have ever switched from conventional to synthetic oil is with older used cars that still ran well but the previous owners failed to change the oil regularly and the crankcase has developed sludge issues. I will temporarily switch to a synthetic because the synthetic additives are great for stripping away sludgy buildup. After a few thousand miles, I switch back to conventional oil and I usually get a few extra oil leaks because the synthetic did such a good job that it stripped away some sludge buildup around weaker seals that it was helping to block oil leaks. I say, if it ain’t broke, don’t fix it. Seems kinda like taking 3-4 extra vitamins every day in hopes you’ll live longer.


#34

K

kinard

My TORO zero turn mower has Kawasaki 23 hp engine. 270 hours on it. 10 Years old. Been using CASTROL 10w30 or 20w50 in it, conventional oil. I've been thinking about maybe running synthetic in it this spring. Heck, everything else seems to be running ir. Got any thoughts on that anyone? I don't think I'd want to go down to 5w30 and don't know if synthetic comes in 10w30 or some such.
I think 5W-30 full synthetic would be fine.


#35

S

skiwithjohn

I have a 1997 Deere 325 garden tractor with a Kawasaki 17hp single cylinder engine. It has about 1900 hours on it. I have been using Mobil 1 10w30 in it since the first oil change. No problems with it. It does not use any oil. I did have to change the main oil seal on the crankshaft at about 1800 hours and should have changed it a few hundred hours sooner.


#36

T

TobyU

To be honest with you and the real world facts... it's not going to matter!
As long as you keep the oil level up and change it somewhat regularly what's in your case once every 2 years would be fine and once every year even more than fine, then the engine is going to outlive the rest of the machine and the hydros etc and any repairs for failures you do have will not be oil related as in low quality of oil or lack of lubrication.
There's a whole lot of strong opinions on synthetic oils and a whole lot of people are in love with the machines and treat them like a collector car or a member of the family etc but the way it really works out, for most people, as I said it won't make a difference.
It will cost you a little more but maybe you'll send your intervals a little longer so you will equal out to be the same and you'll have less time doing it but even if your wallet is a little lighter, it will make you feel better so that's worth it to most people.
But let's be realistic. Your mower is an exact example of what I see from 99 plus percent of my customers.
I say it so many times it's down to almost a sales pitch but I'm not selling anything. Lol
"The average customer plus between 25 and 35 hours a year on their mower unless they mow acreage or more than one lawn or they bag a lot of leaves."
Zero turns get even fewer because despite the claims that they cut your mowing time in half, which they don't, they do speed it up some.
So you have exactly 27 hours a year!!
There could be some disagreement about how many hours these engines should last, or do last but I will tell you that 98% of them that are replaced or deemed to be worn out have plenty of life left in them and are not worn out...but rather they are damaged or they have had a component failure which has nothing to do with oil changes or type of oil.
The fact is the average consumer regardless of what type of mower they have, well typically never see over 400 to 500 hours on it.
It will be replaced before this time either due to age or a needed repair.
I only get a very few that have seven or 800 and occasionally one with 1200 or 1400 hours but then again I don't cater to commercial customers or people with acreage.
Many of these engines are capable of going 2500 plus hours and still not be worn out.
The problems that do happen like head gaskets blowing on Briggs & strattons and valve train issues which happened on both Briggs and Kawasakis too often, have nothing to do with oil or better or worse lubrication etc but rather assembly inconsistencies, the lack of using proper locking mechanisms like a drop of loctite or a lock washer or things valve train but actually had related with slip valve guides or popped valve seats which the vast majority of the time are caused from engines that have overheated because there is massive debris / dirt and oil or nesting or grass build up in the cooling fins so they can't dissipate the heat.
Even though synthetic oil will typically lower the temperature of a machine, it's not going to be enough to prevent a slipped valve guide or a popped valve seat when there is a brick size mass of nesting packed in tight there impeding almost all air flow.
Funny enough, I had a mower that was my pride and joy even though it was old.
You had to breaks vanguard on it which is the best Briggs engine ever made and right up there with Honda and Kawasaki in terms of quality.
I had it for several years and cut much taller grass using it almost as a brush hog instead of a lawn mower so worked it really hard and never had a problem with it.
This is with conventional oil SAE 30.
I switched over to full synthetic and I believe it was Mobil 1 and darn if it didn't slip a valve guide very shortly thereafter!!
Did it cause it? Did it help itto go? I'll never know.
There is a chance that oil was so slippery that it worked its way in there and allowed that five guide to push with less Force even though the heat might have been a little bit lower with the synthetic.
Regardless, I fixed the valve guide and had it back up and running in about an hour because it was on a grasshopper and those things with power taken off both the crankshaft and the top of the flywheel takes a little longer to get the shrouds off...and I went ahead and put the next best thing to synthetic in there.
Valvoline VR1 racing 30 weight.
It has a high zinc content and that's really what I was going for anyways was potential protection from metal to metal contact and it's been running fine ever since with no additional slipped valve guides or problems.
Who knows it would slip another one if I put synthetic back in and still worked it hard like I do because it's got three other guides that are Factory original and untouched.
I'm just going to stick with the VR 1 because it is a great oil.
Now, it's not really the best for long-term use whether that be lots of hours or lots of time but still it's not like it's in a car and the mower doesn't get that much use.

So anyways, knock yourself out but these people putting amsoil in their mowers which I THINK EVERY SINGLE TIME a post of synthetic oil comes up somebody will talk about they only use amsoil and show a picture ad nauseam!!
Yes! Amazon makes some excellent oils and some of them are probably the best synthetics the average person not in the specialty or or oil industry is able to obtain BUT IT'S JUST WAY OVERKILL AND A LOT MORE MONEY!
Any full synthetic brand name you can buy at Walmart, which will probably be your cheapest price, is going to give you anything you could ever hope for innocent so to spend three or four more dollars a quart or even more for amsoil in a lawn mower is simply crazy or if that's offensive to some I'll say it simply wasteful.
Now, as far as the off brands or house brands of full synthetic, they probably aren't quite as good as the popular name brands but they're still leaps and bounds better than a cheap convention oil so you're still getting whatever you're trying to get.
There are a couple of places out there that have some house branded full synthetic made by big rapid little companies that is quite a bit cheaper than what you can buy the brand names for at Walmart in the 5qt jug.
But basically, it's whatever floats your boat because it's all good.
It's far more important to keep the oil at the full mark and check it often!
Low oil damages far too many engines and far more than dirty oil does.


#37

T

TobyU

Tell that to the equipment manufacturers that use synthetic straight from the factory in new equipment. Kohler dealers don't even receive conventional oil from their distributors anymore. The conventional Kohler 10w30 supercedes to the full synthetic version.
This is true but there is a big difference in a brand new engine that has been finished at a factory with far better equipment than someone's going to have if they rebuild one or put new rings in one at home.
A factory finish on the cylinders and new Factory build is also far better and advanced than even the best or largest small engine repair shops will have if they rebuild an engine.
So in this case it can speed things up and be beneficial to start off a fresh rebuild with conventional for at least a few hours and then switch over to synthetic.
Works the same with car engines too when people rebuild them or freshen them up.
A whole lot has changed in that world too over the past 25 years..
Let me know who can relate to this.. back in the day we had a three angle valve job done and thought it was the best thing since sliced bread and all that extra horsepower we were getting from it.
Now, if you were to do a three angle valve job on the average newer vehicle, you would end up with a FAR less sealing valve situation!
You would be making it far worse than when it left the factory.
So what is ideal for fresh new Factory built engines is not necessarily, or even often the same or best for a mechanic rebuild engine.


#38

T

TobyU

At this point, you’re doing your engine a disservice by not using synthetic oil. It’s a much better product than conventional oil. There is no downside other than cost.
I cannot agree.
When you have a decent quality conventional oil in your machine that is kept at the full mark and is not allowed to get excessively dirty, anything beyond that is overkill.
Hardly ever does a residential customer or homeowner "wear out" an engine because they used it so much and put so many hours on it.
If this were the case and let's say you were getting 2,200 hours out of your engine with conventional oil and it was having oil and ring sealing issues ETC then by switching to synthetic on the same engine when you did it again with a new one, if all things remained equal, you could probably go 2,500 maybe 2,700 but I would expect it to go longer.
BUT the point is that just doesn't happen for 99% and even more of homeowners.
They replaced their machine or engine or have it rebuilt because of some other reason!
It's almost always some other reason..
It's almost never low compression due to the rings or the cylinder walls or scuffing of the pistons etc.
So since these quality of oil failures don't really occur, it doesn't really make that much sense to put an over-the-top higher quality oil in there.
Basically all it does is make people feel better.


#39

T

TobyU

I have a Generac 15KW standby generator air cooled with 992cc V twin engine, would it be ok to use the oil mentioned above (Amsoil/Kawasaki) and which one would be better?
Now THIS is an actual or at least potential situation where synthetic oil can be greatly beneficial.
In reality, most people's generators get used very infrequently except for the weekly startup and test that these larger ones have, and when they do actually use them it's only for a few hours until the power comes back on.
But for a whole house generator or any type of generator being used for many hours a day during a long-term power outage, you will quickly exceed the recommended oil change interval!
This is where synthetic can greatly help you and actually give your engine more protection because many people will run a generator 10 to 14 hours a day and some will let one stay on and provide power until it automatically switches back off when the power comes on when it's set up that way.
None of these small engines like this we're designed to go over 100 hours between oil changes and most are under that.
That only gives you a few short days and it's time for an oil change.
Synthetic can certainly increase that interval and not put as much wear and tear on your engine.
Now when you get into diesel engines and such that power some generators, they are designed for much longer use, longer oil change intervals and they go thousands of hours in their lifespan.


#40

T

TobyU

I can't imagine why a superior product would be discouraged. I have used full synthetic in my mower (and car) since the first change. Walmart sells synthetic at a great price and it is highly rated.
Because it's overkill and it costs more.
It's just not needed for most situations.
It would be like putting grade 8 bolts in an application that only required standard grade 2.
It would also be like building an engine for your car, go-kart, or any potential application with a ton more horsepower than you need like let's say 50 to 75% more or even double.
You don't need it and you probably can't even use it so why do you need the extra?
In this case it's even more likely to cause problems because if you over build the engine in some situations then the weak link becomes the transmission, drive shaft (s), motor mounts or even the frame or structure.
With synthetics and lawn Care equipment, about the only negative besides the obvious price, can be increased consumption and leakage or seepage.
It's not as common as it used to be but it certainly does still happen.


#41

T

TobyU

A lot of that thinking about synthetic oil would not allow proper break-in was false. Just the engine manufacturers not committing to the new oils even though a lot of synthetic oils start with the same refined base as the conventional oil they are replacing. Use of conventional oils for the first 50 hours to aid break-in has been removed from the owners manuals. And changing the break-in oil at 5 hours has been eliminated on engines with oil filters,because the break-in debris gets filtered. So the interval is now to go by the first recommended oil change interval so 50-100 hours. Almost all vehicles come from the factory with synthetic oil in the engine. Auto engines don't even have a break-in oil change, and basically never did. My 2011 Ram 1500 uses synthetic oil in everything but the engine. And the reason it doesn't use synthetic in the engine is because the synthetics in the 5w20 oils don't meet the Chrysler oil specs,


The Kohler synthetic oil change kit sourced from Amsoil and has a 300 hour change interval, which in most cases may be excessive. The old 25 357 06-S conventional oil now has been replaced with 25 357 64-S full synthetic. So Kohler doesn't even offer a conventional oil even outside of the synthetic oil service kit that they are pushing sourced from Amsoil.
A lot of the reason they now you synthetic oil from the factory is because the manufacturing procedures and tolerances got much better. They finished the cylinder walls and the ring materials are better so they no longer need conventional oil for things too polish together for a bit to seal properly.
They can build engines so well today that they don't even need a break-in period at all.
That was not the case 25 years ago and it's still not really the case in outdoor power equipment because these engines are low performance little turds.
They don't get nearly as high quality or expensive machines that bore and finish those blocks as an automotive engine does.
They also don't get nearly the expensive or high quality rings etc.


#42

J

Jhon

Not exactly on point, but worth noting when talking about using synthetic oil: The conventional dinosaur stuff works better for breaking in new rings. Otherwise, I only use synthetic.
Good Call. When I purchased a large generator a few years back, I called the manufacturer (Duromax) and asked about using synthetic oil. The Tec said exactly what you said. Run regular oil in it for the first 30 or so hours and then I can switch to synthetic. And that is what I did.
PS, I have a 17 year old John Deere lawn tractor that I ran on John Deere motor oil for most of its life. But I switched to a synthetic blend about 3 years ago and it seems to work fine. I just great a great deal on Castrol EDGE Full Synthetic Engine Oil for 2 bucks a quart from Autozone. So I will eventually switch to that in my tractor.


#43

G

GroundLoop

One of the things missing in conventional dino oil is zinc. If you want to continue using dino oil adding in a zinc additive will help prolong the life. https://revxoil.com/shop/zinc-oil-additive/ My 13 year old Kohler Courage engine in one of the zero turns supposedly has/had a lifetime of 500 hours but I now have surpassed that and the engine still sounds good and the old oil looks good when changed. I have a few old 80's GM performance cars with flat tappet cams and running synthetic is not recommended due to leaks. I have been adding ZDDP for the past 30 years.


#44

P

PGB1

An engine lubrication engineer for one of the car companies told me that if you switch to synthetic on an old engine, do the next oil & filer change sooner to get rid of the newly dissolved & dislodged solids.

For me, just as Crazy Charlie mentioned earlier, old engines start leaking after switching to synthetic. As I understand it, synthetics are very good at cleaning & dislodging the gunk that conventional oil leaves behind. I've not had this problem with semi-synthetic.

Paul


#45

L

lbrac

Conventional Oil is paraffin oil and paraffin equals sludge. I don't need to break an engine in with sludge. Plus with modern metallurgy break-in isn't necessary. I use Rotella T6 5w40 In my briggs engines and also in my generator. The difference is in the detergent package. Rotella is a truck engine oil that uses a longer lasting detergent. I have two riders over 10yrs old that run perfect and don't have any of the problems that I read about here. I change the oil every couple of seasons. No sense in buying extended interval oil and over servicing the equipment. Thats it from a truck mechanic's point of view.
Many years ago, when things were simpler, and much less technical, it was known that Quaker State brand engine oils were refined from paraffin based crude oils from PA. Most other engine oils at the time were asphaltic based. When wet clutches that were lubricated by engine oil were using paraffin based oil, the clutch plates would slip when the paraffin saturated the plates of the clutch, and the plates could also stick together when they cooled. Back then, motorcycle clutches were affected by paraffin based oils more than most equipment. Most oil came from US sources then, but comes from many sources now. I put 500K miles on a 1987 Volvo 245 using various brands of conventional oils without any engine problems, and even valve adjustments were not needed. Oil changes were at 3K miles until I was driving 600+ miles/week, when I went to 5K mile changes. It was still running well when sold. It used a quart of oil between oil changes, partially from minor rear crank seal leaks. Things are more technical these days and relatively minor differences are now known, and sometimes understood; sometimes not.


#46

The Maintenance Guy

The Maintenance Guy

Like the old Pennzoil commercial…motor oil is motor oil 😂. At least when it comes to lawnmowers for me. I pour in whatever I have leftover from oil changes. If it’s a machine dear to your heart and pocketbook though, do whatever the manufacturer recommends. 😊


#47

7394

7394

One place I would not scrimp, would be the mower hydros'... There I add the best oil.


#48

D

Dieselbob

When I bought my new Kohler engine for my Grasshopper two years ago, I contacted Kohler and told them after spending 2K on a new engine, I wanted to use the BEST possible engine oil. Partially due to hard use and partially because the Grasshopper grass collector box sits right over the engine and holds in heat, I had always suffered from diminishing oil pressure in warm weather. ( I always install oil pressure gauges on any engine possible). Kohler set me up with their 10W50 synthetic, and man what a difference! Now I have ZERO oil pressure degradation, and even though I only run it about 110 hours hours, I have eliminated any in season oil changes, plus now no need to change to a lighter oil for winter snow blowing and then back to heavier oil again for mowing season, so I'm actually SAVING money. If most of you guys actually saw what your hot oil pressure was with conventional oil, you would ALL be changing to synthetic.


#49

C

Craiger

I've been using synthetic oil in my cars since 1988. It lubricates better than conventional. Several have gone over 200,000 mi. One big point. Using a synthetic blend makes about as much sense as blending cheap generec local store brand whiskey with super expensive top shelf like Pappy Van Winkle. I've used synthetic oil in all my small engines for many years with success. The additional cost is negated because you don't need to change oil as often. It's a no brainer.


#50

G

GrumpyL5030

My TORO zero turn mower has Kawasaki 23 hp engine. 270 hours on it. 10 Years old. Been using CASTROL 10w30 or 20w50 in it, conventional oil. I've been thinking about maybe running synthetic in it this spring. Heck, everything else seems to be running ir. Got any thoughts on that anyone? I don't think I'd want to go down to 5w30 and don't know if synthetic comes in 10w30 or some such.
I had this question years ago for an old car I had. The answer I got kinda made sense, so I followed that advice:
An older engine with high miles/hours is better off running traditional (non synthetic oil) to prevent loss of compression due to synthetic oil cleaning the cylinder of old, baked on oil products that form with age and miles. The synthetics stand up to heat remarkably and can reduce oil change intervals. The traditional oils might need to be changed more frequent but are less expensive. I'd stick with what you've been doing. Good luck JC.


#51

G

GrumpyL5030

Be very careful about switching from conventional to synthetic on any "not new" engine. Synthetic oils do not have the qualities and additives that keep the gaskets plump and sealed like conventional oils do.I am living proof that trying to take better care of my engines by switching to synthetic did nothing more than start a dripping leak where there was previously no leak.This 1st happened on a 100k mile Jeep which had a privileged babied life .Thought it would be a good idea to switch to synthetic at that time and I immediately discovered that where I may have had some slight seepage ,which is common an gaskets, turned into an immediate leak.I changed the synthetic out immediately within a a few days.The new leak improved with the use of conventional oil however I had slightly leaking gaskets for the next 100k miles.My next Jeep owned from new I used conventional oil except in the cold winter months where my remote start would not crank enough times to start the Jeep with conventional oil so I would schedule a synthetic change just before the cold weather hit so the engine would crank easier with the synthetic and remote start would function.The motor is currently at 150k and I just did the synthetic change ,as I always have ,and noticed that my valve covers started leaking for the 1st time so the synthetic has gotten me again. I think I will add some "stop leak" to the synthetic before changing it to see if any improvement.Stop leak contains concentrated additives that are found in conventional oils so I will give it a try .That being said,I would recommend a synthetic blend over a full synthetic for any engine that is not new.
Now as far as new engines that call for synthetic, they are manufactured with different type of seals and gaskets that are more compatible with synthetic oil use.Charlie
Good advice. I have a 20 year old Kubota 4cyl diesel that's used for snowblowing. I just keep the block heater plugged in and it starts up every time (Damn! I bet I just jinxed myself by saying that).


#52

B

biggertv

Depends on your situation. That expensive beautifully Clean oil could get real Dirty real quick, even with a filter. Unlike the streets, lawns are dirty, some worse than others. I would focus more on frequent oil changes than type of oil. I use Atwoods house brand HD-30 and change when it gets dirty, don't even count hours. I've got an acre of dusty dirty lawn in Texas. If your're cutting manicured lawns in the suburbs, Synthetic could be an option for you.


#53

C

Canuck64

My TORO zero turn mower has Kawasaki 23 hp engine. 270 hours on it. 10 Years old. Been using CASTROL 10w30 or 20w50 in it, conventional oil. I've been thinking about maybe running synthetic in it this spring. Heck, everything else seems to be running ir. Got any thoughts on that anyone? I don't think I'd want to go down to 5w30 and don't know if synthetic comes in 10w30 or some such.
2006 John Deere X300 - 16 HP Kawasaki FH491V V-Twin. Been running Mobile 1 since 2006 approaching 1300 hrs with no engine work. Changed trans to Mobile 1 at 200 hrs, pulled pan at 925 hrs and no visible wear. Tractor does 1.5 grass, spraying chemicals plus misc mtce work in summer and blows snow in winter (Canadian prairie winter). Never plugged in in the winter, just in a garage. Starting to use a little oil between annual changes.

Compression 115 PSI at 925 hrs.
Mobile 1 - 5W30
Oil Filter: WIX 51394
Transmission Oil: Mobil 1 5W50,


#54

J

J.D. Dave

Now THIS is an actual or at least potential situation where synthetic oil can be greatly beneficial.
In reality, most people's generators get used very infrequently except for the weekly startup and test that these larger ones have, and when they do actually use them it's only for a few hours until the power comes back on.
But for a whole house generator or any type of generator being used for many hours a day during a long-term power outage, you will quickly exceed the recommended oil change interval!
This is where synthetic can greatly help you and actually give your engine more protection because many people will run a generator 10 to 14 hours a day and some will let one stay on and provide power until it automatically switches back off when the power comes on when it's set up that way.
None of these small engines like this we're designed to go over 100 hours between oil changes and most are under that.
That only gives you a few short days and it's time for an oil change.
Synthetic can certainly increase that interval and not put as much wear and tear on your engine.
Now when you get into diesel engines and such that power some generators, they are designed for much longer use, longer oil change intervals and they go thousands of hours in their lifespan.
Thank you very much for your reply, this is what I wanted to know.
Have a Happy and Healthy New Year


#55

E

edporch

I have a Kohler 27hp on my 2008 Grasshopper and I always use Mobil 1 10w-30.
Haven't had any problems.


#56

T

TobyU

When I bought my new Kohler engine for my Grasshopper two years ago, I contacted Kohler and told them after spending 2K on a new engine, I wanted to use the BEST possible engine oil. Partially due to hard use and partially because the Grasshopper grass collector box sits right over the engine and holds in heat, I had always suffered from diminishing oil pressure in warm weather. ( I always install oil pressure gauges on any engine possible). Kohler set me up with their 10W50 synthetic, and man what a difference! Now I have ZERO oil pressure degradation, and even though I only run it about 110 hours hours, I have eliminated any in season oil changes, plus now no need to change to a lighter oil for winter snow blowing and then back to heavier oil again for mowing season, so I'm actually SAVING money. If most of you guys actually saw what your hot oil pressure was with conventional oil, you would ALL be changing to synthetic.
How many hours a year do you put on your machine?
I have some my suspicions as to what the number probably is so please humor me.
In reality, no one needs to actually see what their oil pressure is because it doesn't really matter.
Remember that for decades these engines lasted for 30 and 40 years and had no pressure lubrication at all so they had zero oil pressure. Lol
As I've stated before, and many times, the average owner is never going to notice a life expectancy difference regardless of what type of oil they use.
Hardly any engine failures or short engine lives are due to the type of oil or even the dirtiness of the oil but rather the lack of enough of it.
You may not be the typical owner though.


#57

D

Dieselbob

How many hours a year do you put on your machine?
I have some my suspicions as to what the number probably is so please humor me.
In reality, no one needs to actually see what their oil pressure is because it doesn't really matter.
Remember that for decades these engines lasted for 30 and 40 years and had no pressure lubrication at all so they had zero oil pressure. Lol
As I've stated before, and many times, the average owner is never going to notice a life expectancy difference regardless of what type of oil they use.
Hardly any engine failures or short engine lives are due to the type of oil or even the dirtiness of the oil but rather the lack of enough of it.
You may not be the typical owner though.
My typical year is 110-130 hours, with 90% being grass and leaf pickup and 10% being snow blowing. I was running conventional HD 30 in the summer, and 5W30 in the winter (unit is stored in unheated out building). When I was using conventional oil in hot dry weather, I was often seeing oil pressure drop from 50 PSI cold to 20-25 PSI hot. While you are correct that splash lubrication worked for years, engines with pressure lubrication NEED pressure, and in my opinion, an air cooled engine screaming at 3600 RPM needs more than 25 LBS. I lost my original engine at 1600 hours, proceeded by notable oil consumption and finally a hole in a piston. Since installing the new engine and using the 10W50, the engine runs the same 50 PSI no matter how hot it is or how long I run it, it doesn't use a drop of oil all year long and and it starts just fine in zero degree weather. As I said, I also eliminated any in mowing season oil changes, and the seasonal change to-from heavy oil and light oil, so it makes life a LOT easier, even running the oil 1/3 of it's advertised life. It is costing me around $30 per year in oil (2 Qts) and 1 filter, where as I was was using 4-6 Qts. of conventional per year PLUS a fair amount of add oil and 2-3 filters, so the change to synthetic was a no brainer for me. I also couldn't disagree more that you don't need to see your oil pressure. I want to know what is going on with my engines at ALL times, so I can monitor performance and try to avoid catastrophic failures. I can tell when the fan screen on my Kohler's is covered with debris just by the oil pressure gauge. I also installed a volt gauge on my Grasshopper so I don't get surprised by charging system issues, and I installed oil and volt gauges on my Kubota BX 2230 that came with neither too. Knowledge is power, and I want EVERY BIT of information I can get at my disposal.


#58

B

bertsmobile1

One of the things missing in conventional dino oil is zinc. If you want to continue using dino oil adding in a zinc additive will help prolong the life. https://revxoil.com/shop/zinc-oil-additive/ My 13 year old Kohler Courage engine in one of the zero turns supposedly has/had a lifetime of 500 hours but I now have surpassed that and the engine still sounds good and the old oil looks good when changed. I have a few old 80's GM performance cars with flat tappet cams and running synthetic is not recommended due to leaks. I have been adding ZDDP for the past 30 years.
You have been spending way too much time on social media
Name one single place in a mower engine where the scuffing force is so high it needs that added protection of zinc.
Now if you are talking about a 2000hp monster truck engine with high lift cams and double valve springs that is a different matter all together .
I really wish people would not post stuff they pull off auto engine sites and post it on mower engine sites because about 1% is relevant, occasionally .


#59

J

jcworks

One place I would not scrimp, would be the mower hydros'... There I add the best oil.
Agree totally


#60

G

Gunn308

Quote from Duromax generator set up manual "Use 20 oz standard oil to fill crankcase" says standard oil 3 more times in manual and gives weights for temp ranges. Oil change procedure says standard oil. this could be a game changer for warrantee work when using synthetics.


#61

7394

7394

this could be a game changer for warrantee work when using synthetics.
Yea, that could be, any reason to void a warranty.


#62

A

Abbeville

Discussing which oil to use is like discussing politics, almost everyone has an opinion and there will always be differences of opinion. I study the owners manual and the engine repair manual and use the charts shown to make a decision. I use Schaeffer 30W synthetic blend (I buy it in 5 gallon pails) in all my small engines, unless the manual specifies something else. Where I live it doesn't get real cold in winter but does get hot in the summer.


#63

J

Jimmy the Lock

OK to use synthetic oil ?

Yes, synthetic oil is best... Amsoil is the way to go! thumbsup2.gif
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#64

J

Jimmy the Lock


I recently purchased a 2023 Spartan Mower RZ-HD 54 in that has a Kawasaki FR691V 23 hp engine.

The oil change kits Spartan sells contains Kawasaki 10w40 oil

I'll probably be switching to Amsoil 10w30


#65

H

Have_Blue

My TORO zero turn mower has Kawasaki 23 hp engine. 270 hours on it. 10 Years old. Been using CASTROL 10w30 or 20w50 in it, conventional oil. I've been thinking about maybe running synthetic in it this spring. Heck, everything else seems to be running ir. Got any thoughts on that anyone? I don't think I'd want to go down to 5w30 and don't know if synthetic comes in 10w30 or some such.
I started using the cheapest, thickest (10W-30) synthetic at about 120 hours. It never smoked or used oil, and the oil stayed clean. Now at 235 hours, and there are no changes so it seems to be fine. I doubt that it adds more than 1 season to a homeowner's machine, but it's so cheap, why not?


#66

H

Have_Blue

If your engine does not need synthetic to protect for extreme heat or slow flow when cold, then you can use conventional oil without any problems. OTOH, if you want to spend more per oil change, synthetic is perfectly fine to use.
The engine was designed with conventional oil as the prospective lubricant. It should do fine. Synthetic will not buy anything unless you reach temperature extremes where regular oil would tend to degrade.
I have yet to use any synthetic in my Kohler CVs, with conventional 10W30 as the spec'd lube. They have lasted since 1988 and 1997 respectively, don't knock or use oil between changes. I do not baby them, as they were designed to run at about 3k rpm for hours, and they do fine. When drained, the oil is still brown, not black. I use any brand, whatever is on the shelf. I have used Stens filters without problem, along with some from auto parts stores that matched.
This is not rocket science, and the oils today have better additive packages than when the engines were designed.
If you want to spend money on very very high quality oils, have at it. You are just lining the pockets of those who sell that product. Check with "Project Farm" YT channel for unbiased comparisons of oil brands. You may be surprised at which seem to perform better than some usual suspects. Oil should not cost $10/qt. If it does, a LOT of that is in profit.
IMO.
tom
Spoken for truth! Todd knows his business! I use Wal-Mart Super Tech because it stacks up well with the expensive brands, and costs less than some conventional and blends. If it's better and costs a few pennies more, why not use it?


#67

StarTech

StarTech

Just be aware there are equipment out there that Synthetic can't be used in. Honda ATVs is one of them due the clutching system.


#68

7394

7394

Truth. 👆


#69

J

Jimmy the Lock

Discussing which oil to use is like discussing politics

No, there's actually ways to scientifically test motor oil whereas politicians are all ignorant ramuses

Not all oil is the same which cannot be said about the politicians


#70

J

Jimmy the Lock

I'd recommend Kawasaki K-TECH, it's synthetic blend and is formulated for small air cooled engines. I service several commercial Z turns with well over 3K hours on the clock with it. since new....
If you're dead set with full synthetic, i'd look no further than Amsoils 10w30 small engine oil https://www.amsoil.com/p/amsoil-10w-30-100-synthetic-small-engine-oil-ase/


That's the good stuff there ya'll
smile-grin4.gif


#71

J

Jimmy the Lock

Just use regular oil and put in a bottle of slick 50.

I thought they changed the name to Slick Willie ?


#72

S

Skippydiesel

Speculation:

I understand that synthetic oils have better temperature resistance to breakdown.
I do not know if this applies to all synthetic oils but know of one engine maker, who has addressed high temperatures, in one of their models by specifying that a synthetic oil (meeting very specific standards) be used. all their other engines use semi synthetic blends.
I note that Kawasaki has recommended (not obliged) synthetic multigrade oil for use in their twin cylinder engines.
This does not mean that mineral oils are not perfectly adequate in most small motor applications.


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